Portable electronic devices (e.g. notebook computers, cellular telephone, cordless telephones mobile data terminals, radio frequency portable communication devices, etc.) typically include a rechargeable battery that is charged by a recharging unit plugged into an AC power source, such as that found in conventional 115 VAC lines. The recharging unit powers the portable device, while simultaneously charging the rechargeable battery. The portable device switches over to battery power upon removal of the portable device from the charging unit or the power source. Most intelligent portable devices employ a bridge battery that is utilized during the removable of the main rechargeable battery when it powers the portable device. The main function of the bridge battery is to insure that data stored in a Random Access Memory (RAM) device is not lost during swapping of the rechargeable battery. The bridge battery is usually a much smaller battery because during a battery swap, the portable device normally will enter a low current or suspend mode, so that most current drawn from the bridge battery is used to refresh the RAM device, until a new main battery is installed into the device.
Many portable devices employ complicated switching or logic circuitry when changing from the rechargeable device power to the main battery power, and from the main battery power to the bridge battery power. The switching or logic circuitry takes up valuable space on a circuit board that could be utilized to perform the functions of the portable device. In some cases, additional circuit boards are necessary to house the switching or logic circuitry. This increases the size and cost of the portable device. Furthermore, some of these portable devices employ expensive power management and supervisory circuitry to cause the functional components in the portable device to enter different modes, depending on the type of unit powering the portable device or the current status of the unit powering the portable device. The additional power management and supervisory circuitry adds to the size, the cost and also to the complexity of the portable device.
Accordingly, there is a strong need in the art for a system and/or method that can provide power distribution for a portable electronic device at low cost, while reducing space utilized in employing such a system.